GRAV® Clear Coil Water PipeGRAV Clear Coil Water Pipe Experience the ultimate in clean, smooth hits with the GRAV Clear Coil Water Pipe. This exceptional piece features a coil perc and a fixed downstem, providing a double dose of cooling and cleaning for an unparalleled smoking experience. Coil perc for initial smoke filtration Delivers incredibly smooth hits Comes with a 14mm GRAV Funnel Bowl Best performance with approximately 3" of water